INFO: task syz.4.805:14691 blocked for more than 143 seconds.
Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.805 state:D stack:21480 pid:14691 tgid:14688 ppid:12322 task_flags:0x400140 flags:0x00000004
Call Trace:
context_switch kernel/sched/core.c:5382 [inline]
__schedule+0x168f/0x4c70 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x165/0x360 kernel/sched/core.c:6860
schedule_preempt_disabled+0x13/0x30 kernel/sched/core.c:6917
rwsem_down_write_slowpath+0xbec/0x1030 kernel/locking/rwsem.c:1176
__down_write_common kernel/locking/rwsem.c:1304 [inline]
__down_write kernel/locking/rwsem.c:1313 [inline]
down_write_nested+0x1b5/0x200 kernel/locking/rwsem.c:1694
inode_lock_nested include/linux/fs.h:902 [inline]
filename_create+0x1f9/0x470 fs/namei.c:4132
do_mkdirat+0xa0/0x590 fs/namei.c:4384
__do_sys_mkdirat fs/namei.c:4409 [inline]
__se_sys_mkdirat fs/namei.c:4407 [inline]
__x64_sys_mkdirat+0x87/0xa0 fs/namei.c:4407
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb731d8e969
RSP: 002b:00007fb732b44038 EFLAGS: 00000246 ORIG_RAX: 0000000000000102
RAX: ffffffffffffffda RBX: 00007fb731fb5fa0 RCX: 00007fb731d8e969
RDX: 0000000000000000 RSI: 0000200000000340 RDI: ffffffffffffff9c
RBP: 00007fb731e10ab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007fb731fb5fa0 R15: 00007ffff47e6638
Showing all locks held in the system:
3 locks held by kworker/0:0/9:
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a080d48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc900000e7c60 (deferred_process_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900000e7c60 (deferred_process_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: switchdev_deferred_process_work+0xe/0x20 net/switchdev/switchdev.c:104
1 lock held by khungtaskd/31:
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:331 [inline]
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:841 [inline]
#0: ffffffff8df3dce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6764
3 locks held by kworker/u8:5/1157:
#0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801a089148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc900041ffc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc900041ffc60 ((linkwatch_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: linkwatch_event+0xe/0x60 net/core/link_watch.c:303
5 locks held by kworker/u8:7/4467:
#0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88801aef3948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc9000e237c60 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc9000e237c60 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2d84d0 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0x145/0xbd0 net/core/net_namespace.c:608
#3: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: cleanup_net+0x611/0xbd0 net/core/net_namespace.c:644
#4: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock kernel/rcu/tree_exp.h:304 [inline]
#4: ffffffff8df437b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2f4/0x730 kernel/rcu/tree_exp.h:998
2 locks held by dhcpcd/5482:
#0: ffffffff8f2c9ae8 (vlan_ioctl_mutex){+.+.}-{4:4}, at: sock_ioctl+0x5ee/0x790 net/socket.c:1273
#1: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: vlan_ioctl_handler+0xd0/0x650 net/8021q/vlan.c:554
2 locks held by getty/5580:
#0: ffff8880353ea0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
#1: ffffc90002ffe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400 drivers/tty/n_tty.c:2222
3 locks held by kworker/u8:9/7291:
#0: ffff88814da99948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3213 [inline]
#0: ffff88814da99948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_scheduled_works+0x9b1/0x17a0 kernel/workqueue.c:3319
#1: ffffc90005027c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3214 [inline]
#1: ffffc90005027c60 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ec/0x17a0 kernel/workqueue.c:3319
#2: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: rtnl_net_lock include/linux/rtnetlink.h:130 [inline]
#2: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: addrconf_dad_work+0x112/0x14b0 net/ipv6/addrconf.c:4198
2 locks held by syz.4.805/14691:
#0: ffff88803c51c420 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff88805cbe6b98 (&sb->s_type->i_mutex_key#28/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
#1: ffff88805cbe6b98 (&sb->s_type->i_mutex_key#28/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4132
5 locks held by syz.4.805/14718:
#0: ffff88803c51c420 (sb_writers#23){.+.+}-{0:0}, at: mnt_want_write+0x41/0x90 fs/namespace.c:556
#1: ffff88805cbe6b98 (&sb->s_type->i_mutex_key#28/1){+.+.}-{4:4}, at: inode_lock_nested include/linux/fs.h:902 [inline]
#1: ffff88805cbe6b98 (&sb->s_type->i_mutex_key#28/1){+.+.}-{4:4}, at: filename_create+0x1f9/0x470 fs/namei.c:4132
#2: ffff88805cbe6f80 (&inode->ei_update_lock){+.+.}-{4:4}, at: __bch2_create+0x2f2/0xb90 fs/bcachefs/fs.c:569
#3: ffff888038c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_lock_acquire include/linux/srcu.h:161 [inline]
#3: ffff888038c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: srcu_read_lock include/linux/srcu.h:253 [inline]
#3: ffff888038c04228 (&c->btree_trans_barrier){.+.+}-{0:0}, at: __bch2_trans_get+0x806/0xda0 fs/bcachefs/btree_iter.c:3385
#4: ffff888038c26590 (&c->gc_lock){++++}-{4:4}, at: bch2_btree_update_start+0x68f/0x14c0 fs/bcachefs/btree_update_interior.c:1179
2 locks held by bch-copygc/loop/14714:
2 locks held by syz-executor/17144:
#0: ffffffff8f2d84d0 (pernet_ops_rwsem){++++}-{4:4}, at: copy_net_ns+0x317/0x590 net/core/net_namespace.c:514
#1: ffffffff8f2e5008 (rtnl_mutex){+.+.}-{4:4}, at: ip_tunnel_init_net+0x2ab/0x800 net/ipv4/ip_tunnel.c:1160
1 lock held by syz.5.1043/17174:
=============================================
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 31 Comm: khungtaskd Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
nmi_cpu_backtrace+0x39e/0x3d0 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x17a/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:158 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:274 [inline]
watchdog+0xfee/0x1030 kernel/hung_task.c:437
kthread+0x70e/0x8a0 kernel/kthread.c:464
ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 17174 Comm: syz.5.1043 Not tainted 6.15.0-rc6-syzkaller-00052-g9f35e33144ae #0 PREEMPT(full)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
RIP: 0010:rcu_rnp_online_cpus kernel/rcu/tree.c:3943 [inline]
RIP: 0010:rcu_rdp_cpu_online kernel/rcu/tree.c:3953 [inline]
RIP: 0010:rcu_lockdep_current_cpu_online+0xbf/0x120 kernel/rcu/tree.c:3994
Code: 18 48 89 d8 48 c1 e8 03 42 80 3c 30 00 74 08 48 89 df e8 f4 64 78 00 48 8b 1b 48 83 c3 70 48 89 d8 48 c1 e8 03 42 80 3c 30 00 <74> 08 48 89 df e8 d7 64 78 00 4c 85 3b 75 1a 48 c7 c7 40 39 f4 8d
RSP: 0018:ffffc9000bbc7468 EFLAGS: 00000246
RAX: 1ffffffff1be8616 RBX: ffffffff8df430b0 RCX: e4538583e96bf000
RDX: ffffc90011c01000 RSI: ffffffff8bc104c0 RDI: ffff8880b893a9a0
RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: ffffffff822aa67a R12: 0000000000000100
R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000002
FS: 00007fa10f4816c0(0000) GS:ffff8881261fb000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa104dff000 CR3: 0000000064ffa000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
rcu_read_lock_held_common kernel/rcu/update.c:113 [inline]
rcu_read_lock_held+0x1e/0x50 kernel/rcu/update.c:349
lookup_page_ext mm/page_ext.c:254 [inline]
page_ext_lookup+0xe2/0x160 mm/page_ext.c:520
page_ext_iter_begin include/linux/page_ext.h:132 [inline]
__page_table_check_zero+0x16e/0x510 mm/page_table_check.c:139
page_table_check_free include/linux/page_table_check.h:41 [inline]
free_pages_prepare mm/page_alloc.c:1263 [inline]
free_unref_folios+0xb84/0x1490 mm/page_alloc.c:2782
folios_put_refs+0x559/0x640 mm/swap.c:992
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x49e/0x14b0 mm/shmem.c:1125
shmem_truncate_range mm/shmem.c:1237 [inline]
shmem_evict_inode+0x272/0xa70 mm/shmem.c:1365
evict+0x504/0x9c0 fs/inode.c:810
__dentry_kill+0x209/0x660 fs/dcache.c:660
dput+0x19f/0x2b0 fs/dcache.c:902
__fput+0x68e/0xa70 fs/file_table.c:473
fput_close_sync+0x119/0x200 fs/file_table.c:570
__do_sys_close fs/open.c:1581 [inline]
__se_sys_close fs/open.c:1566 [inline]
__x64_sys_close+0x7f/0x110 fs/open.c:1566
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xf6/0x210 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fa10e58d5ca
Code: 48 3d 00 f0 ff ff 77 48 c3 0f 1f 80 00 00 00 00 48 83 ec 18 89 7c 24 0c e8 43 91 02 00 8b 7c 24 0c 89 c2 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 36 89 d7 89 44 24 0c e8 a3 91 02 00 8b 44 24
RSP: 002b:00007fa10f480e00 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00000000ffffffff RCX: 00007fa10e58d5ca
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000008
RBP: 0000000000000010 R08: 0000000000000000 R09: 0000000000004462
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000008
R13: 00007fa10f480ef0 R14: 00007fa10f480eb0 R15: 00007fa103e00000